English Original Sentence
The boy is sick, though he doesn’t appear so.
parezca→parece [?]
The boy is sick, though he doesn’t appear so.
parezca→parece [?]
The boy is sick, though he doesn’t appear so.
after aunque an imperfecto form of verb is used (parezca)
But parezca is present subjunctive.
If I recall correctly, the rule is:
Spelling: When a verb has an irregular stem in the first person singular in the Presente de Indicativo, we use this irregular stem to form the whole of the Presente de subjuntivo.
Subjuntivo: hypothetical or contrary-to-fact situation: the child is sick, but does not show it.